The present invention relates to liquid electrolytic batteries and, more particularly, to a fluid supply system for replenishing liquid electrolyte in the batteries.
Battery-powered vehicles, such as, for example, golf carts and utility vehicles, require periodic charging of the batteries and replenishment of liquid electrolyte in the batteries. Typically, the filling systems and procedures require connection of the system to a fluid source, either pressurized or in a vacuum arrangement, the source being located offboard the vehicle. Flow of fluid through the system is caused by pressurized supply fluid or a vacuum applied to the filling system.
One problem with the above-described filling devices and procedures is that a separate fluid hook-up step is required before the liquid electrolyte can be replenished in the batteries.
Another problem with the above-described filling systems and procedures is that a separate source of pressure is required to supply fluid to the filling system. Such a separate pressurized source may be a pump or a vacuum connected to the filling system.
Yet another problem with the above-described filling systems and procedures is that, each time the batteries are replenished with fluid, the separate fluid source must be connected to the filling system, and fluid must be replenished, even if only a small amount of fluid must be replenished.
The present invention provides a system for supplying fluid to a battery, a vehicle and a method for supplying fluid to a battery which substantially alleviate one or more of the above described and other problems with the existing filling systems and procedures. More particularly, the present invention provides a fluid supply system in which the gas produced during charging causes fluid flow through the system.
In particular, the present invention provides a system for supplying fluid to a battery in a vehicle powered by the battery, the vehicle including a vehicle frame supporting the battery, the battery including a battery cell, fluid being transmittable to the cell, gas generated during charging of the battery being transmittable out of the cell. The system is defined as including a tank for holding fluid, and a hydraulic circuit connecting the battery to the tank. The hydraulic circuit is defined as including an inlet conduit connectable between the tank and the cell, and an outlet conduit connectable between the cell and the tank, gas produced during charging of the battery causing fluid flow through the outlet conduit and to the tank. Preferably, the outlet conduit collects gas transmitted from the cell in the form of gas bubbles with fluid entrapped between the bubbles, whereby the bubbles flow to the tank due to pressure build-up in the battery causing flow of fluid through the hydraulic circuit during charging.
Also, the present invention provides a system for supplying fluid to a battery in a vehicle powered by a first battery and a second battery. The system is defined as including a tank for holding fluid, and a hydraulic circuit connecting the tank to the first battery and to the second battery. The hydraulic circuit is defined as including a first inlet conduit between the tank and the first battery cell, and a first outlet conduit between the first battery cell and the tank, gas produced during charging causing fluid flow through the first outlet conduit and to the tank. The hydraulic circuit is defined as further including a second inlet conduit between the tank and the second battery cell, and a second outlet conduit between the second battery cell and the tank, gas produced during charging causing fluid flow through the second outlet conduit and to the tank.
Preferably, the hydraulic circuit has a first hydraulic circuit portion including the first inlet conduit and the first outlet conduit and a second hydraulic circuit portion including the second inlet conduit and the second outlet conduit. In some constructions, the first hydraulic circuit portion and the second hydraulic circuit portion provide separate, parallel hydraulic circuit portions. In other constructions, the first hydraulic circuit portion and the second hydraulic circuit portion are arranged in series.
In addition, the present invention provides a system for supplying fluid to battery, the system including a first tank for holding fluid, a second tank for holding fluid, and a hydraulic circuit connecting the battery to the first tank and to the second tank. The hydraulic circuit is defined as including a first conduit connectable between the first tank and the cell, a second conduit connectable between the cell and the second tank, and a third conduit connectable between the second tank and the first tank. The second tank is defined as collecting excess fluid supplied to the cell during fluid replenishment of the cell and collecting gas produced during charging, the gas causing fluid to move from the second tank to the first tank. Preferably, after charging, the second tank collects excess fluid supplied to the cell during fluid replenishment of the cell.
Further, the present invention provides a vehicle including a vehicle frame supported for movement over ground, an electric motor supported by the vehicle frame and operable to drive the vehicle, a battery supported by the vehicle frame and electrically connectable with the motor to selectively power the motor, the battery including a battery cell, fluid being transmittable to the cell, gas generated during charging of the battery being transmittable out of the cell, a tank for holding fluid, and a hydraulic circuit connecting the battery to the tank. The hydraulic circuit is defined as including an inlet conduit connectable between the tank and the cell, and an outlet conduit connectable between the cell and the tank, gas produced during charging causing fluid flow through the outlet conduit and to the tank.
Also, the present invention provides a vehicle including a vehicle frame, an electric motor, a first battery and a second battery supported by the vehicle frame and electrically connectable with the motor to selectively power the motor, the first battery including a first battery cell, the second battery including a second battery cell, fluid being transmittable to the first battery cell and to the second battery cell, gas generated during charging being transmittable out of the first battery cell and out of the second battery cell, a tank for holding fluid, a hydraulic circuit connecting the first battery and the second battery to the tank. The hydraulic circuit is defined as including a first inlet conduit connectable between the tank and the first battery cell, a first outlet conduit connectable between the first battery cell and the tank, gas produced during charging causing fluid flow through the first outlet conduit into the tank, a second inlet conduit connectable between the tank and the second battery cell, and a second outlet conduit connectable between the second battery cell and the tank, gas produced during charging causing fluid flow through the second outlet conduit and to the tank.
In addition, the present invention provides a vehicle including a vehicle frame supported for movement over ground, an electric motor supported by the vehicle frame and operable to selectively drive the vehicle, a battery supported by the vehicle frame and electrically connectable with the motor to selectively power the motor, the battery including a battery cell, fluid being transmittable to the cell, gas generated during charging of the battery being transmittable out of the cell, a first tank for holding fluid, a second tank for holding fluid and a hydraulic circuit connecting the battery to the first tank and to the second tank. The hydraulic circuit is defined as including a first conduit connectable between the first tank and the cell, a second conduit connectable between the cell and the second tank, and a third conduit connectable between the second tank and the first tank. The second tank is defined as collecting excess fluid supplied to the cell during fluid replenishment of the cell. The second tank is defined as collecting gas produced during charging of the battery, the gas causing fluid to move from the second tank to the first tank.
Further, the present invention provides a tank for holding fluid in a fluid supply system, the fluid supply system supplying fluid to a battery in a vehicle selectively powered by the battery, the vehicle including a vehicle frame supporting the battery, the battery including a battery cell, the fluid supply system including a hydraulic circuit, the hydraulic circuit including an inlet conduit connected to the cell and an outlet conduit connected to the cell. The tank is defined as including a container for holding fluid and defining a tank outlet and a tank inlet, the tank inlet being below the tank outlet, the tank outlet being connected with the inlet conduit, the tank inlet being connected with the outlet conduit, the container having a bottom wall, a tube having an inlet end positioned adjacent the tank inlet and an outlet end positioned above the inlet end, the inlet end being spaced above the bottom wall, a portion of the outlet conduit extending into the inlet end, and a tray supported adjacent the outlet end of the tube and communicating with the tank outlet. Gas produced during charging of the battery flows from the outlet conduit into the tube, causing fluid to move from the tube into the tray by percolation. Fluid in the tray flows into the inlet conduit.
Also, the present invention provides a tank for holding fluid in a fluid supply system, the tank including a container for holding fluid and defining a tank outlet, a vent outlet and a tank inlet. The tank outlet is defined as being connected to the inlet conduit, and the tank inlet is defined as being connected with the outlet conduit. The container is defined as including a container wall providing a first container portion and a second container portion, the tank outlet being in the first container portion, the tank inlet and the vent outlet being in the second container portion. Initially, a first container portion pressure and a second container portion pressure are substantially equal. Thereafter, gas produced during charging of the battery is vented from the second container portion causing a pressure differential of the second container portion pressure being less than the first container portion pressure, the pressure differential causing fluid flow from the first container portion, through the hydraulic circuit and to the second container portion.
In addition, the present invention provides a tank for holding fluid in a fluid supply system, the tank is defined as including a first container portion defining a fill inlet for receiving fluid into the system, and a second container portion in fluid communication with the first container portion and defining a return inlet connected to the outlet conduit such that fluid and gas flow into the second container portion, the second container portion also defining a vent outlet operable to allow gas to vent from the system, one of the first container portion and the second container portion including a fluid supply outlet connected to the inlet conduit to supply fluid to the battery.
Further, the present invention provides a method for supplying fluid to a battery in a vehicle selectively powered by the battery. The method is defined as including the acts of providing a system for supplying fluid to the battery, the system including a tank for holding fluid and a hydraulic circuit connecting the battery to the tank, the hydraulic circuit including an inlet conduit connectable between the tank and the cell, and an outlet conduit connectable between the cell and the tank, supplying fluid to the tank, allowing fluid flow from the tank through the inlet conduit to the cell, charging the battery, the charging act including producing gas, an causing flow of fluid through the outlet conduit and to the tank, the causing act including using gas produced during the charging act to cause fluid flow through the outlet conduit and to the tank.
Also, the present invention provides a method for supplying fluid to a battery in a vehicle selectively powered by a first battery and a second battery. The method is defined as including the acts of providing a system for supplying fluid to the battery, this system including a tank for holding fluid, and a hydraulic circuit connecting the battery to the tank, the hydraulic circuit including a first inlet conduit connectable between the tank and the first battery cell, a first outlet conduit connectable between the first battery cell and the tank, a second inlet conduit connectable between the tank and the battery cell, and a second outlet conduit connectable between the second battery cell and the tank, supplying fluid to the tank, allowing fluid flow from the tank through the first inlet conduit to the first battery cell, allowing fluid flow from the tank through the second inlet conduit to the second battery cell, charging the first battery and the second battery, the charging act including producing gas, and causing flow of fluid through the first outlet conduit and to the tank and through the second outlet conduit and to the tank, the causing act including using gas produced during the charging act to cause fluid flow through the first outlet conduit and through the tank and through the second outlet conduit and to the tank.
In addition, the present invention provides a method for supplying fluid to a battery in a vehicle selectively powered by the battery, the method including the acts of providing a system for supplying fluid to the battery, the system including a first tank for holding fluid, a second tank for holding fluid, and a hydraulic circuit connecting the battery to the first tank and to the second tank, the hydraulic circuit including a first conduit connectable between the first tank and the cell, a second conduit connectable between the cell and the second tank, and a third conduit connectable between the second tank and the first tank, supplying fluid to the first tank, allowing fluid flow from the first tank through the first conduit to the cell, allowing excess fluid to flow through the second conduit into the second tank, charging the battery, the charging act including producing gas, and causing flow of fluid from the second tank, through the third conduit and to the first tank, the causing act including using gas produced during the charging act to cause fluid flow through the third conduit and to the first tank.
One independent advantage of the present invention is that, in some constructions, the fluid source is supported on the vehicle. Therefore, a separate fluid hook-up step is not required before the liquid electrolyte can be replenished in the batteries. The fluid supply system may automatically replenish the batteries.
Another independent advantage of the present invention is that, in some constructions, the fluid supply system utilizes the pressure of the gas produced during charging to cause fluid flow through the fluid supply system. Therefore, a separate source of pressure, such as a pump or a vacuum, is not required.
Yet another independent advantage of the present invention is that, in some constructions, the fluid supply system automatically replenishes the necessary fluid to the batteries when necessary and each time the batteries are to be replenished. The operator is only required to add fluid to the system when no fluid remains in the fluid source after replenishment.
Other independent features and independent advantages of the present invention are apparent to those skilled in the art upon review the following detailed description, claims and drawings.